1. Field of the Invention
This invention relates to an endless drive track for propelling a snowmobile, or the like, and more particularly, to a new and improved traction stud force distributing backer member for stabilizing and positioning a traction stud mounted on an endless drive track.
2. Description of the Prior Art and Objects
Track driven vehicles such as snowmobiles are typically propelled by an endless, flexible drive track which is trained around a pair of sprocket wheels, at least one of which is rotatably driven by a gasoline operated engine. The track, which typically comprises a rubber drive belt, includes an upper run generally parallel to a lower run which engages the surface to be traversed and integral traction lugs projecting outwardly from the outer surface of the belt. Such traction lugs can be effective in certain conditions, such as snow, to improve the traction capability of the belt, however, when the snowmobile is traversing hard slippery terrain, such as ice, the integral rubber lugs are substantially less effective.
To improve the traction capabilities of the endless snowmobile drive track, simple elongate threaded bolts were first mounted in apertures cut through the track. The head of each bolt was disposed on the inside face of the endless belt and the terminal end, which was sharpened, projected outwardly beyond the outer face of the belt to provide a sharpened point that penetrated the ice and improved the traction capability. A force distributing washer was applied to the shank of the bolt and threaded fasteners held the washers to the outer face of the track to equally distribute forces exerted by the stud on the belt over a larger portion of the track to inhibit the bolt from xe2x80x9cpulling throughxe2x80x9d the track.
To further improve the traction capabilities of track driven vehicles traveling over hard surfaces, such as ice, traction studs have been developed such as that illustrated in U.S. Pat. No. 3,973,808 issued to Roger G. Janson, et al, on Aug. 10, 1976, and assigned to the applicant, as well as U.S. Pat. No. 4,218,101 issued to James A. Thompson on Aug. 19, 1980.
A so-called xe2x80x9cT-nutxe2x80x9d stud was developed as illustrated in U.S. Pat. No. 3,838,894 issued to Donald G. Reedy on Oct. 1, 1974. The Reedy stud included an axially outer end having a sharpened point thereon, an axially inner threaded end having a T-shaped nut threaded thereon with a transverse flange bearing against the inner surface of the track, and an intermediate flange on the outer surface of the track. A stud stabilizing dished washer was mounted between the intermediate flange and the outer track surface for distributing forces exerted on the stud over a broad area on the outer surface of the track.
Thereafter, so-called xe2x80x9cpush-thruxe2x80x9d studs were developed as illustrated in applicant""s U.S. Pat. No. 5,234,266, issued to James R. Musselman and Brian D. Musselman on Aug. 10, 1993, as well as U.S. Pat. No. 5,641,214 issued to Glen E. Kafka on Jun. 24, 1997. Each of the latter two-mentioned patents disclose dished or dome shaped force distributing plate receiving a stud extending generally perpendicular to the plane of the lower run of the track so as to be vertically disposed as the stud passes along the lower track run. These force distributing plates have commonly been referred to in the art as xe2x80x9cbacker platesxe2x80x9d. Each of these backer members includes an aperture there-through which is axially aligned with the center and/or center line of the backer member so that the force transmitted to the shank of the stud is equally distributed about the perimetrical edge of the backer plate rim that bears against the underside of the lower track run.
A flexible snowmobile drive track typically includes a plurality of longitudinally spaced apart stud mounting track sections coupled together by integral lug mounting sections which mount the aforementioned integral traction lugs that project outwardly beyond the outer faces of the lug mounting sections. The traction studs are mounted on the stud mounting sections between the lugs and have sharp terminal ends which project outwardly beyond the adjacent outer terminal ends of rubber track lugs for penetrating the ice over which the lower track run travels.
When the tracks incorporating the prior art vertically disposed studs, such as that illustrated in the Kafka U.S. Pat. No. 5,641,214 starts to move in its endless path, the sharp ice penetrating points on the lower track run penetrate the ice to obtain purchase and to transmit traction increasing forces between the track mounting section and the icy terrain whereby the stud mounting track sections will flex relative to the adjacent lug mounting sections to vertically inclined positions and the terminal ends of each stud will tilt forwardly, in the direction of the forward travel of the vehicle being propelled and rearwardly relative to the direction of track travel, to a forwardly downwardly inclined position. The forward tilting, relative to the direction of vehicle travel, decreases the effectiveness of the traction stud. Accordingly, it is an object of the present invention to provide new and novel apparatus for increasing the traction capability of a traction stud for an endless vehicle drive belt.
Yet another object of the present invention is to provide a new and novel traction assembly for an endless snowmobile belt which will increase the traction capabilities of a snowmobile drive belt.
It is another object of the present invention to provide a new and novel device for mounting T-nut and push-thru traction studs at a rearwardly downwardly inclined attitude relative to the direction of travel of the vehicle being propelled.
It is still another object of the present invention to provide a new and novel force distributing backer plate for stabilizing a traction stud including an aperture therethrough for receiving the stud at a downwardly forwardly inclined attitude relative to the direction of track travel and a rearwardly downwardly inclined altitude relative to the direction of the snowmobile.
It is yet another object of the present invention to provide a new and novel stud stabilizing and positioning backer member which will detachably receive the shank of the stud at a predetermined angle relative to the plane of the lower run of the track in a no-load position.
It is a further object of the present invention to provide a new and novel stud stabilizing and positioning force distributing backer member which will position either push-thru or T-nut studs on the track so as to be forwardly downwardly inclined on the lower run of the track relative to the direction of the track travel, when the track is in a no-load rest position and vertical, when the track is under load.
A still further object of the present invention is to provide a force distributing stud stabilizing and positioning backer member which will mount on the outer face of the track and includes an aperture therein for disposing a track mounted stud at a predetermined angle relative to a vertical line when the track is not under load but a lesser predetermined forward angle when the track is under load.
Another object of the present invention is to provide a stud stabilizing and positioning backer member which includes a hub defining a hollow inwardly opening cavity having a terminal rim lying in a predetermined plane and an aperture through the hub which is inclined at an angle relative to a line perpendicular to the plane.
A still further object of the present invention is to provide a force distributing stud stabilizing and positioning member of the type described which includes a hollow side wall with a lower portion and an upwardly outwardly inclined terminal side wall portion defining an upwardly opening cavity and terminating in a rim which lies in a plane for bearing against the outer face of the lower run of an endless drive belt and an aperture in the side wall which receives the shank of the stud at a predetermined angle relative to a line perpendicular to the plane of the rim.
Still another object of the present invention is to provide a stud stabilizing and positioning backer member which includes a hollow enclosure wall provided with an aperture there-through that receives the shank of a traction stud to dispose the stud downwardly forwardly in the direction of track travel when the track is in a no-load rest position and a lesser downwardly forwardly inclined position when the track is traveling under load.
A still further object of the present invention is to provide a traction stud stabilizing and positioning backer member having a hollow enclosure wall defining an inwardly opening cavity and provided with an aperture there-through which receives the shank of the stud to dispose the outer terminal end of the stud a predetermined distance forwardly, in the direction of track travel, of the axially inner end of the stud when the track is in a no-load rest position but a lesser predetermined distance forwardly of the inner end when the track is forwardly traveling under load.
The studs of the type disclosed herein are typically and regularly utilized by snowmobile racers. The Snowmobile Racing Association dictates the maximum static distance which the terminal end of the traction stud can project outwardly beyond the terminal ends of the adjacent flexible traction lugs that project outwardly of the outer track face. These distances can vary between different racing classes but typically would be in the range of xe2x85x9c inch to xc2xe inch. One of the reasons for this rule is that studs which project outwardly beyond the outer terminal end of the flexible track studs are considered to provide increased traction advantages. In the prior art backer plate, such as that disclosed in the aforementioned U.S. Pat. No. 3,838,894, which mounts the stud perpendicular to the plane of the rim of the backer plate and perpendicular to the lower run of the track in the rest position, the stud, under load, will tilt and the distance between the terminal end of the stud and the adjacent flexible track lugs will decrease as the track is driven under dynamic load and thus the traction capability is decreased compared to the traction when the stud is perpendicular. Accordingly, it is an object of the present invention to provide a new and novel traction assembly for an endless snowmobile drive belt which will increase the distance which the terminal stud end projects beyond the adjacent flexible track lugs when the track is under load to forwardly propel the snowmobile.
It is another object of the present invention to dynamically move the stud tip outwardly relative to its static position on the track.
It is yet another object of the present invention to provide a traction stud stabilizing and positioning backer member which will mount the traction stud so that the terminal end of the stud projects a predetermined distance beyond the adjacent flexible track lugs when the track is in a no load rest position but will extend a greater predetermined distance outwardly beyond the terminal end of the track lug when the track is in a load condition forwardly propelling the snowmobile.
Other traction increasing products have been attempted heretofore such as that manufactured by the Saber Corporation under the trademark xe2x80x9cHaucker Platexe2x80x9d, model number HS-22 and disclosed at page 16 of the Saber Traction Products 2001 Catalog published by Saber Traction Products W197 N7555 F and W Court, Lannon Wis. 53046. This construction includes a plate coupled to the outside face of the track by an inwardly projecting threaded bolt and mounting a pair of outwardly projecting studs at an angle. This prior art Saber device illustrated in the aforementioned catalog has the disadvantage that the dual studs will sometimes cause the plate to rotate about the axis of the threaded mounting bolt to destroy the traction capability.
U.S. Pat. No. 5,980,001 issued to Edward R. Rubel on Nov. 9, 1999, also discloses a push-through stud having a terminal surface penetrating end disposed at an angle relative to the shank of the stud, however, this patent does not disclose or remotely suggest the concept of a backer plate having an offset mounting aperture for receiving the shank of the stud. The backer plate constructed according to the present invention provides rigidity to keep the stud from tipping in an unwanted direction relative to the track. The new force distributing backer plate constructed according to the present invention also distributes the force applied to the shank over a broad area. Accordingly, it is another object of the present invention is to provide a new and novel backer plate member which will mount a stud at an inclined attack angle and will maintain the angle if the stud rotates, about its longitudinal axis relative to the track.
A further object of the present invention is to provide a force distributing plate member of the type described which will allow the stud to rotate about its axis and yet continue to maintain a forward angle of attack relative to the direction of track travel.
It is another object of the present invention to provide a new and novel stud mounting force distributing backer member having a forwardly offset aperture there-through which will mount the shank of the stud outwardly forwardly, relative to the direction of track travel, such that the longitudinal axis of the stud is at an angle relative to a line perpendicular to the plane of the rim in the range of 3 degrees to 11 degrees.
It is another object of the present invention to provide a new and novel stud mounting backer member having a forwardly offset aperture there-through which will mount the shank of the stud outwardly forwardly, relative to the direction of track travel, such that the longitudinal axis of the stud is at an angle relative to a line perpendicular to the plane of the rim in the range of 4 degrees to 10 degrees.
Still another object of the present invention is to provide a traction stud mounting backer member of the type described including a hollow hub uniformly formed about a central axis mounting a traction stud with a trailing attitude relative to the direction of the travel of the snowmobile, when the snowmobile is at rest and a lesser attitude when the snowmobile is moving forwardly.
A further object of the present invention is to provide a new and novel traction assembly which includes a stud stabilizing and positioning backer member having a hollow enclosure wall defining an inwardly opening cavity and an aperture there-through for mounting the shank of the stud at an angle relative to a vertical line when the drive belt is in a normal rest position and vertical when the track is under load to forwardly propel a snowmobile.
It is yet another object of the present invention to provide a new and novel endless drive belt for propelling a snowmobile or the like including a new and novel traction assembly including a new and novel backer plate member having a hollow enclosure wall provided with a terminal rim which lies in a predetermined plane and an aperture in the enclosure wall which receives the shank of a stud mounted on the track at an angle relative to a line perpendicular to the plane of the rim.
Still yet another object of the present invention is to provide an endless snowmobile drive belt of the type described including a new and novel traction assembly incorporating a new and novel backer plate which has a curvilinear, dome shaped hub having a center axis, a uniformly shaped sidewall extending about the center axis and terminating in a rim which lies in a predetermined plane, and an eccentrically disposed aperture provided in the sidewall for mounting a traction stud, which is received by the track, at an angle relative to the lower run of the track when the snowmobile is at rest but at a lesser angle when the snowmobile is under load.
It is another object of the present invention is to provide a new and novel one-piece backer plate including a base having leading and trailing edges lying in a first plane and an intermediate portion integrally spanning the leading and trailing edges and including a rearwardly outwardly inclined, relative to the direction of track travel, forward shank receiving portion adjacent the leading edge and having a shank receiving aperture extending therethrough for receiving the stud.
A further object of the present invention is to provide a one-piece backer plate of the type described including a base having leading and trailing edges and an intermediate portion spanning the leading and trailing edges including a shank receiving portion adjacent the leading edge lying in a rearwardly outwardly inclined plane relative to the direction of track travel.
Yet another object of the present invention is to provide a backer plate of the type described wherein the base includes a perimetrical flange extending around a forwardly outwardly inclined stud receiving member which lies in a forwardly outwardly inclined plane relative to the plane of the rim and the direction of travel of the snowmobile being propelled.
Another object of the present invention is to provide a one-piece backer plate of the type described including a rearwardly outwardly inclined, in the direction of track travel, shank receiving portion which mounts the shank of a snowmobile stud for to-and-fro swinging movement about a transverse fulcrum axis transverse to the shank of the stud.
Still another object of the present invention is to provide a traction assembly of the type described which forces the confronting track rubber forwardly to the front of the dome in the direction of track travel to increase stud support.
Still another object of the present invention is to provide a one-piece backer plate of the type described including a base having leading and trailing edges lying in a plane and having an axis equidistant between the leading and trailing edges and an intermediate portion, integrally spanning the leading and trailing edges including a rearwardly outwardly inclined, in the direction of track travel, forward eccentrically disposed shank receiving portion for receiving the shank of the stud.
Another object of the present invention to is provide a traction assembly of the type described which will not increase the stopping distance of a snowmobile.
Still yet another object of the present invention is to provide an improved traction assembly of the type described which will improve acceleration of a snowmobile.
A still further object of the present invention is to provide a new and improved backer plate of the type described which can be utilized with existing traction studs.
Another object of the present invention is to provide a backer plate of the type described wherein the rearwardly outwardly inclined stud mounting portion extends from a position adjacent the leading edge to a position rearward of the centerline of the backer plate.
These and other objects of the present invention will become more readily apparent to those of ordinary skill in the art as the description thereof proceeds:
A force distributing, stud stabilizing backer member for positioning and stabilizing an elongate traction stud mounted on the lower run of an endless drive belt which forwardly propels a belt driven vehicle; the traction stud including a longitudinal axis, an axially inner upper end mounted on the endless drive belt, and an outer, lower terrain engageable end; the force distributing stud stabilizer member including: a hollow enclosure wall defining an inwardly upwardly opening belt receiving cavity and terminating in a rim lying in a predetermined plane, the wall including a stud mounting aperture there-through for detachably receiving the shank of the stud in a downwardly rearwardly position when the belt is in a rest condition and a lesser downwardly rearwardly inclined position when the belt is under load forwardly propelling the vehicle.